Titanium alloys



n Patented Jan. 13, 1959 According to the present invention, therefore, a series of valuable titanium base alloys is provided having the 2868540 following range of composition, namely:

ALLOYS Percent, igiclusiyg A t James Morris Butler, -Moseley, Birmingham, England, 5 533; :53 1 20 assignor to The British Non-Ferrous :Metals'Research to 0 Association, London, England, amassociation of Great 1 Icon 0 B i Manganese to Molybdenum 0 to 5.0 No Drawing. Application January 11, '1955 V i 0 to 5 Sena] 4815263 Titanium Remainder 7 Claims (CL 75-1755) In Table I the behaviour of some ternary and quaternary alloys of the invention on hot-working by rolling This invention relates to new and improved titanium at 1000 alld in Creep tests at and base alloys and their'uSeinindUsn-yj is compared with that of some known titanium-alumin- For many purposes it is desirable toproduceatita'nium m all y contaimng sllicon 0r molybdenum but no base alloy capable of being easily hot-worked d poszirconium. The creep resistance is expressed as thestress sessing good creep-resistant properties at temperatures in tons/in? required to produce an extension of 1% in of the order of 400 C. V v 500 hours at the temperature specified.

Table I Titanium alloy containing- Creep test at Behaviour on rolling Al, Si, Zr, Mo, Mn, 400 0. 500 0. Percent Percent Percent Percent Percent Known Alloys 5.0 0.5 fair; some edge crack- 34-36 12-14 mg. 5.0 1.0 5.0 1 5.0 e.-- 5 18-20 5.0 10

Alloys of the Invention 17-19 5.0 0.25 s W. 18-21 5.0 0.1 10 18-20 5.0 1o 15-17 5.0 5 15-17 In apaper entitled Titanium Alloy Development pre- The superiority of the alloys of the invention is evisented by M. Hansen and H. D. Kesseler in January 1953, dent. The ternary titanium-aluminium-zirconium alloys to the American Society of Automotive Engineers, the show a markedly better combination of hot-working prop- P P of titamum base alloys Curfel1t 11Se erties and creep-resistance than the known titanium base and these authors Q F l :alloys and the quaternary alloys combine a good healumlmum'molybdenum and tltamulfn'alumfmufn'slhcon havionr on hot-rolling with a very good creep-resistance alloys are among the most creep-resistant titanium base especially at 5000 C. 85 i to d th t tit b H Moreover these quaternary alloys have a superior duce ave now mm a amum ase a oys tility in the as-rolled condition as compared with known sisting (apart from iron, nitrogen, oxygen and carbon which may be adventitiously present and must not exceed 0.25% each) of from 310% of aluminium and from 1-20% zirconium, the balance being titanium, exhibit a markedly better combination of hot-working properties and creep-resistance than titanium base alloys in use heretofore.

titanium-aluminium-molybdenum or titanium-aluminiumsilicon alloys, the ductility of which is not readily improved by heat-treatment.

In the quaternary alloys part of the silicon, manganese, molybdenum, or vanadium may be replaced by one or more of the other three components and, provided W hav al f und th t th properties are ill the total composition is within the range above specified, further enhanced by the inclusion of one or more of th ult p alloys have ar y enhanced the following components, namely: properties.

Percent Table II shows the results of creep tests on three Silicon P to titanium base alloys containing 5.0% aluminium and, Manganese P to respectively, 5% of molybdenum, 0.5% of silicon and Molybfienum UP to 10% of zirconium, the results being expressed as per- Vanadmm UP to centage strains after 300 hours at 400 C. under stresses the balance in each case being titanium. of 25 and 20 tons per square inch.

The superiority of the titanium-aluminium-Zirconium alloy of the invention is apparent.

The low density and relatively high resistance to creep of the alloys of the invention make them attractive for use in industry, e. g. for gas turbine and other engine components which are required to operate at temperatures up to about 400 C., particularly Where such components are subjected in service to stresses arising from inertia forces.

I claim:

1. An engine component capable of withstanding about 400 C. which is required to have high creep resistance due to inertia forces and which is made of a titanium base alloy which, apart from iron, nitrogen, oxygen and carbon present in amounts not exceeding 0.25% each, consists essentially of about: 3 to 10% aluminum, 1 to 20% zirconium with at least one metal of the group consisting of silicon, manganese, molybdenum and vanadium present in amounts up to 0.5 in the case of silicon, up to 5% in the case of manganese, up to 5% in the case of molybdenum and up to 5% in the case of vanadium, the creep resistance of the alloy being at least 40 tons per square inch at 400 C.

2. A titanium base alloy which apart from iron, nitrogen, oxygen and carbon present in amounts not exceeding 0.25% each, consists essentially of about 3 to 10% aluminum, 1 to 20% zirconium with at least one metal 1 of the group consisting of silicon, manganese, molybdenum and vanadium present in significant amounts up to 0.5% in the case of silicon, up to 5 in the case of manganesefup t o 5% in the case of molybdenum and up to 5% in the case of vanadium, the creep resistance of the alloy being at least 40 tons per square inch at 400 C.

3. A titanium base alloy consisting of, apart from iron, nitrogen, oxygen and carbon present in amounts not exceeding 0.25% each, 5% of aluminum and 5% of zirconium, together with 0.1% of silicon, the remainder being titanium.

4. A titanium base alloy consisting of, apart from iron, nitrogen, oxygen and carbon present in amounts not exceeding 0.25% each, 5% of aluminum and 5% of zirconium, together with 0.25% of silicon, the remainder being titanium.

5. A titanium base alloy consisting of, apart from iron, nitrogen, oxygen and carbon present in amounts not exceeding 0.25% each, 5% of aluminum and 10% of zirconium, together with 0.1% of silicon, the remainder being titanium.

6. A titanium base alloy consisting of, apart from iron, nitrogen, oxygen and carbon present in amounts not exceeding 0.25% each, 5% of aluminum and 10% of zirconium, together with 1% of manganese, the remainder being titanium.

7. A titanium base alloy consisting of, apart from iron, nitrogen, oxygen and carbon present in amounts not exceeding 0.25% each, 5% of aluminum, 5% of zirconium, together With 1% of molybdenum, the remainder being titanium.

References Cited in the file of this patent UNITED STATES PATENTS 2,669,513 Jafree Feb. 16, 1954 2,703,278 Finlay et a1. Mar. 1, 1955 2,704,251 Vordahl Mar. 15, 1955 2,754,204 Jatfee et a1. July 10, 1956 2,754,205 Jafiee et a1. July 10, 1956 FOREIGN PATENTS 718,822 Germany Feb. 26, 1942 

1. AN ENGINE COMPONENT CAPABLE OF WITHSTANDING ABOUT 400* C. WHICH IS REQUIRED TO HAVE HIGH CREEP RESISTANCE DUE TO INERTIA FORCES AND WHICH IS MADE OF A TITANIUM BASE ALLOY WHICH, APART FROM IRON, NITROGEN, OXYGEN AND CARBON PRESENT IN AMOUNTS NOT EXCEEDING 0.25% EACH, CONSISTS ESSENTIALLY OF ABOUT: 3 TO 10% ALUMINUM, 1 TO 20% ZIRCONIUM WITH AT LEAST ONE METAL OF THE GROUP CONSISTING OF SILICON, MANGANESE, MOLYBDENUM AND VANADIUM PRESENT IN AMOUNTS UP TO 0.5% IN THE CASE OF SILICON, UP TO 5% IN THE CASE OF MANGANESE, UP TO 5% IN THE CASE OF MOLYBDENUM AND UP TO 5% IN THE CASE OF VANADIUM, THE CREEP RESISTANCE OF THE ALLOY BEING AT LEAST 40 TONS PER SQUARE INCH AT 400* C. 